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Dishwasher air gap

| Posted in General Discussion on February 1, 2004 06:20am

Howdee ya’ll;

Talk about fixing something that ain’t broke. The drain hose of my friends dish washer discharged into the garbage disposer inlet. This hose was tied up to the underside of the counter (with just a twist tie) so waste water wouldn’t drain back into the dish washer. To improve on this, I installed a standard air gap device  on the sink surface next to the sink faucet. I hooked it up the standard way. No one seems to know anything about these devices. Now I have a secure set up,BUT  when the dish washer drains, some water comes out of the air gap vent and safely drains into the sink. Can anybody tells me what this is all about? Thanks much.

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Replies

  1. MrBill | Feb 01, 2004 06:28pm | #1

    Joe,

     The only time I have seen this happen on ours is when we put too much soap in the dishwasher and the "suds" are too much for the air gap and some of them foam out of the side.  Also .. make sure the air gap is complete .. if the little "cap" is missing from the end of the tube, it will make a mess.

    Hope this helps,

    Bill Koustenis

    Advanced Automotive Machine

    Waldorf Md

    1. joekaye | Feb 02, 2004 04:02am | #4

      Thanks, Mr. Bill, for this information.

  2. DaveRicheson | Feb 01, 2004 08:27pm | #2

    That ussually happens when the discharge hose is partialy clogged up. Could also be a clog at the hookup to the disposal. Most air gaps have a 7/8" inlet and 5/8" discharge. The gunk that gets mulched in the dishwasher hit that bottel neck and just naturally wants to jamb up in the smaller hose. Same thing occurs at the disposal fitting.  It is a PITA to routinely need to clean out that hose.

    The only reason the air gap is required in many areas is so you won,t suck the gunk out of the dishwasher bottom when you are running water through the sink drain. The little bit of water in the dishwasher bottom is a self trap feature that is suppose to block gasses  like a standard trap does.

    Dave

    1. joekaye | Feb 02, 2004 04:01am | #3

      Thanks, Dave, for the 411. J.K.

    2. rjgogo | Feb 02, 2004 10:20pm | #6

      Never had a dishwasher  before and will be installing one in a couple of weeks.  As this is along the thread,  One additional question.  If I route the hose above the high water level in the sink I should be able to get away without needing an air gap.  This from the installation manual. 

       Any compelling reason I should install an air gap.  I would rather not as it is just one more hole in the counter top. 

      1. User avater
        NickNukeEm | Feb 02, 2004 10:45pm | #7

        I've had them with and without, installed them with and without.  The only compelling reason to install them is if your building department requires them.  It's not an issue here, as long as the discharge hose it looped tight under the counter. 

        I never met a tool I didn't like!

        1. edwardh1 | Feb 03, 2004 12:18am | #8

          the air gap device is really ugly.

          I have not seen one ever in Coastal south carolina.

      2. user-222107 | Feb 03, 2004 03:12am | #9

        FYI

        If dishwasher drains into a disposal, code (plumbing) requires an air gap.  Just ran into this myself w/ the inspector and verified in the code book.  However install directions never mention it.  Make your own judgement I guess....

      3. DaveRicheson | Feb 03, 2004 04:09am | #10

        As mentioned by others, local code dictates. I have installed both ways, and even made up some inovative drains over the years. With a disposal, it is almost always required. Code here requires them on all installs, but many remodels don't get them unless they are inspected. HD sells a drain line kit here with and without air gaps. Ask the sales assistant about them, and got one of those HD (how dumb) looks.

        Dave

        1. caseyr | Feb 03, 2004 07:50am | #13

          What is the preferred/best way to run a dishwasher discharge into the waste line if you don't go through the mechanical pig? 

          1. User avater
            BillHartmann | Feb 03, 2004 09:15am | #15

            My sink has a tailpipe has a small side connect which forms a T. The DW is connected to that.

            I always that was standard until I kept seeing all of these remarks about people connected to the GD.

            I don't see any reason to connect the GD. Anything that the DW pump can handle doesn't need to go through the GD and the detergant isn't good on them.

      4. ccal | Feb 03, 2004 07:50am | #12

        Have seen hundreds and installed dozens of dishwashers, never seen an air gap device outside of a magazine. If local code doesnt require it i dont see any reason for it, even then I dont think you need it.

      5. Pd5190 | Feb 03, 2004 08:06am | #14

        I installed a dishwasher last year and put in an airgap because that is what you see in all new installs in So Calif. It leaked from the very first test run of the dishwasher. I disconnected it and have not had a problem. one day I will re route my discharge hose up high like I am supposed to have it.

      6. steve | Feb 03, 2004 11:49pm | #16

        i've installed hundreds of dishwashers and never used an airgap device

        the're not required in ontario canada, so why anywhere else?

        ps i wouldnt run the drain into a garburator, the soap from a dw is very caustic and i've see garb. housings ruined by corrosioncaulking is not a piece of trim

  3. BARMIL48 | Feb 02, 2004 09:24pm | #5

    I was noticing water in my basement below the DW above, so I checked to see if it came out while the DW was running. Sure enough, it did. The problem was that on the lower left side of the DW (Kenmore) where the water supply went from the valve into the cabinet, there was an air gap device open to the atmosphere, and when that had accumulated some mineral deposits, the water was spitting back out onto the floor. I sealed the air gap with caulk, and no more problem. DW works fine, also. I was this close to pulling the DW and replacing it, as I just couldn't figure out where it was leaking by just looking under the kick panel. This feature wasn't mentioned in the manual, either, and, of course, nobody I spoke with at Sears had the slightest.

  4. ahneedhelp | Feb 03, 2004 05:53am | #11

    Besides the technical info/explanation you will receive regarding air gaps, one thing to consider is to make sure the homeowners aren't using too much detergent.

    This is a very common mistake, which can cause oversudsing and in some cases faster residue buildup on plastic interior diswashers.

    I had dishwasher discharge backing up into the drain for many years in our house and blamed it on the way things were plumbed under the sink during a kitchen remodel by the previous owners.

    One day I decided to get myself a drain snake and ran it as far as I could go - about 25'.

    No more backups.

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